JP2005251770A - Manufacturing method of anisotropic conductive connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an anisotropic conductive connector for efficiently manufacturing the anisotropic conductive connector that has high connection reliability of a connected object and a structure in which axes of a plurality of conductive passages penetrating in the thickness direction of a film substrate have an angle with respect to the perpendicular of the main surface of the film substrate. <P>SOLUTION: A roll-like material formed by integrating an insulating film and a conductive filament on a core material is separated from the core material, this is cut to form a flat plate material, and then a plurality of films 10A having conductive filaments are cut out of the flat plate material. Next, the plurality of films with the conductive filaments are stacked such that conductive filaments 2 between the adjacent films are mutually parallel, the obtained stacked body is heated and pressurized, and the obtained block is cut in predetermined thickness, along a plane crossing the conductive filaments 2 with an angle. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing an anisotropic conductive connector, and more particularly to a method for manufacturing an anisotropic conductive connector having a structure in which a conduction path is inclined and penetrated in the thickness direction of a film substrate.

  In recent years, anisotropic conductive connectors have been widely used to electrically connect electronic components such as semiconductor elements (IC chips) and circuit boards. Conventionally, anisotropic conductive connectors have been known to be formed by dispersing conductive fine particles in an insulating film, but this anisotropic conductive connector is structurally connected with a fine pitch connection object. There is a problem that it is difficult to connect, and a terminal of a connection object, for example, an electrode of a semiconductor element or the like must be convex (bump shape). Therefore, as an anisotropic conductive connector capable of solving such problems, that is, a fine pitch and bumpless, the present applicant has disclosed a plurality of conductive paths in an insulating film substrate in International Publication No. WO 98/07216. An anisotropic conductive connector (film) has been proposed in which are insulated from each other and penetrated in the thickness direction of the film substrate.

  By the way, anisotropic conductive connectors are roughly used in the following two applications. One is a so-called mounting type, in which an anisotropic conductive connector is interposed between an electronic component such as a semiconductor element and a circuit board and thermocompression bonded to both to electrically and mechanically connect the electronic component and the circuit board. It is used as a connector. The other is in the functional inspection of electronic components such as semiconductor elements, an anisotropically conductive connector is inserted between the electronic component and the circuit board and pressed against both, so that the electronic component and the circuit board are electrically connected so as to be inspected. It is used as a connector for inspection.

  An anisotropic conductive connector is used as an inspection connector because the electronic component is inspected after the electronic component is mounted on the circuit board. If the electronic component is defective, it is a non-defective product. This is because the circuit board is also disposed of, the yield of the circuit board is lowered, and the amount of money is increased.

  In the inspection of an electronic component such as a semiconductor element, it is necessary to bring the anisotropic conductive connector into contact with the electronic component and the circuit board with a lower pressure in order to prevent damage to the terminal and deformation of the terminal. Therefore, the present applicant, in the above-mentioned International Publication No. WO98 / 07216, arranges a plurality of conductive paths penetrating in the thickness direction of the film substrate so that the axis thereof forms an angle with respect to the normal of the main surface of the film substrate. An anisotropic conductive connector with a different structure is proposed. That is, by placing a plurality of conduction paths that penetrate in the thickness direction of the film substrate in a state inclined in a certain direction, the electronic component is placed on the circuit substrate via the anisotropic conductive connector, and the electronic component is pressed from above. In this case, the conduction path is broken, and the pressure applied to the electronic component and the circuit board is reduced.

  Such an anisotropic conductive connector has conventionally been manufactured by the method described in the above-mentioned International Publication WO98 / 07216, that is, by winding multiple insulation conductive wires (metal wires coated with an insulating resin layer) around the core material, A winding block in which the coating layers are joined so as not to be separated is manufactured, and this block is sliced (cut) to a desired film thickness with a plane that forms an angle with respect to each insulated conductor (metal wire) as a cut surface. It was produced by the method. However, in the conventional manufacturing method, since the insulated conductors are wound in multiple layers, the winding directions of the insulated conductors (metal wires) in the winding block are not easily aligned in a certain direction. Therefore, the direction of inclination of the plurality of conductive paths in the anisotropic conductive connector obtained by cutting the winding block is not uniform, and the direction in which the conductive paths form when the anisotropic conductive connector is pressed varies. Therefore, when the variation in contact pressure with the connection object (circuit board, semiconductor element) in the anisotropic conductive connector increases (decrease in uniformity), the connection reliability with the connection object decreases. There is. Also, when cutting the winding block, set the cutting surface so that the insulated conductor (metal wire) forms an angle with respect to the perpendicular to the cutting surface (that is, the block axis is oblique to the cutting blade) When the block is cut in this way, the film size (size) of multiple anisotropically conductive connectors obtained by cutting out varies, and to unify the film size Therefore, post-processing must be performed. Therefore, there is a problem that an anisotropic conductive connector having a desired size cannot be efficiently manufactured.

In view of the above circumstances, the present invention is an anisotropic conductive connector having a structure in which the axes of a plurality of conduction paths penetrating in the thickness direction of a film substrate form an angle with respect to a normal to the main surface of the film substrate. An anisotropic conductive connector that can efficiently manufacture an anisotropic conductive connector that has a small variation in the inclination direction between the conductive paths (direction in which the conductive path is formed) and that provides high connection reliability with respect to an object to be connected. An object is to provide a manufacturing method.
In addition, an anisotropic conductive connector that has a small variation in the direction of inclination between the plurality of conductive paths (direction in which the conductive paths are formed) and that provides high connection reliability with respect to a connection target, has a desired film size. It aims at providing the manufacturing method of the anisotropically conductive connector which can be manufactured efficiently.

In order to achieve the above object, the present invention has the following features.
(1) A method of manufacturing an anisotropic conductive connector having a structure in which axes of a plurality of conduction paths penetrating in a thickness direction of a film substrate form an angle with respect to a normal to a main surface of the film substrate, An insulating film is wound around the outer periphery, and then a conductive wire is wound spirally around the periphery of the insulating film at a constant pitch, or a conductive wire is wound around the outer periphery of the core material at a constant pitch, After winding the insulating film so as to cover the conductive wire, heat and pressure are applied to integrate the insulating film and the conductive wire on the core, and then the insulating film and the conductive After removing the roll-like material obtained by integrating with the wire from the core material, cutting it into a flat plate, cut out a plurality of films with conductive wires from the flat plate, Adhere multiple films with conductive wire adjacent to each other. The conductive wires between the two layers are stacked so that they are parallel to each other, and the resulting stack is heated and pressurized to create a block in which a plurality of films with conductive wires are integrated. A method for manufacturing an anisotropic conductive connector, wherein an anisotropic conductive connector is obtained by cutting a block into a predetermined film thickness with a plane intersecting the conductive wire at an angle as a cross section.
(2) A plurality of films with conductive wires are shaped so that the main surface of the insulating film has a straight side, and the axes of the plurality of conductive wires are predetermined with respect to the straight side. And a plurality of films with conductive wires are stacked so that the linear sides of adjacent insulating films are stacked in parallel to form a stack, and further obtained from the stack The block according to (1) above, wherein the block is cut into a predetermined film thickness with a plane perpendicular to the linear end side of the block derived from the linear side of the main surface of the insulating film as a cross section. Manufacturing method of anisotropic conductive connector.
(3) The insulating film and the conductive wire wound around the core material are placed in a space where a vacuum or vacuum state can be formed together with the core material, and the space is reduced in pressure or vacuum, and then heated and pressurized. And manufacturing the anisotropic conductive connector according to (1) or (2) above, wherein the insulating film and the conductive wire are integrated on the core.
(4) The method for manufacturing an anisotropic conductive connector according to (3), wherein the space capable of forming the reduced pressure or vacuum state is an internal space of a bag body made of a flexible film.
(5) The anisotropic conductive connector according to (3) or (4), wherein the pressurization is performed by introducing a compressed gas into a space where the reduced pressure or vacuum state can be formed. Production method.
(6) The above (1), wherein the stack is disposed in a space where a reduced pressure or a vacuum state can be formed, and the stack is heated and pressurized after being reduced in pressure or vacuum. The manufacturing method of the anisotropically conductive connector in any one of-(5).
(7) The method for manufacturing an anisotropic conductive connector according to claim 6, wherein the space capable of forming a reduced pressure or vacuum state is an internal space of a bag body made of a flexible film.
(8) The stack is stored in a heat-resistant box having a size such that a slight gap is formed between the inner surface of the stack and the side of the stack. The stack is placed in an internal space of a bag made of a flexible film together with a conductive box, and the space is depressurized or vacuumed, and then heated and pressurized to the stack. (6) The method for producing an anisotropic conductive connector according to (6).

  In this specification, “the main surface of the film substrate” means the surfaces at both ends in the thickness direction of the film substrate, and “the main surface of the insulating film” means the surfaces at both ends in the thickness direction of the insulating film. It should be noted that the terms “film substrate surface” and “insulating film surface” refer to “film substrate main surface” and “insulating film main surface” unless otherwise specified.

Hereinafter, the present invention will be described in detail with reference to the drawings.
The anisotropically conductive connector manufactured by the present invention has a plurality of conductors penetrating in the thickness direction of the film substrate 50 (the direction of arrow A in FIG. 11B) shown in FIGS. 11A and 11B. This is an anisotropic conductive connector 60 having a structure in which the passage 51 is arranged such that its axis L10 forms an angle (α) with respect to the perpendicular L20 of the main surface 50a (50b) of the film substrate 50. Here, FIG. 11A is a plan view, and FIG. 11B is a cross-sectional view taken along line XIb-XIb in FIG. In the drawing, D1 and D2 are first and second directions perpendicular to the conduction path 51 in the anisotropic conductive connector (the direction of the arrow X and the direction of the arrow Y in the main surface 50a of the film substrate 50). Is the pitch.

  The angle (α) formed by the plurality of conduction paths 51 (axial center L10) with the perpendicular L20 of the main surface 50a of the film substrate 50 is generally a connection object (electronic component, circuit board) due to the bending of the conduction paths 51. Is preferably 5 degrees or more so that the effect of reducing the pressure on the two is sufficiently obtained, and if the angle is too large, two objects to be electrically connected (for example, an electronic component and a circuit board) Therefore, the angle is preferably 45 degrees or less.

  The anisotropically conductive connector manufactured by the present invention is particularly preferable as an inspection connector, and the thickness of the film substrate 50 is generally about 20 to 1000 μm, preferably about 50 to 500 μm. The cross-sectional shape of the conduction path may be circular, polygonal, or other shapes, and is not particularly limited. However, a circular shape is preferable from the viewpoint of connection reliability with the connection target (terminal). In addition, the diameter (thickness) is generally 10 to 80 μm when the cross-sectional shape is circular in terms of connection reliability with the connection object (terminal), conductivity of the conduction path itself (electric resistance), and the like. The diameter is preferably about 12 to 60 μm, and when the cross-sectional shape is a polygon or other shapes, the diameter (thickness) of which the cross-section is an area corresponding to the area of a circle having a diameter within the above range Is appropriate. Further, the pitch of the conduction paths 51 (D1 and D2 in the figure) is generally 20 from the viewpoint of connection reliability with the connection target (terminals) and deformability (flexibility) of the anisotropic conductive connector, respectively. -200 micrometers is preferable, Most preferably, it is 20-150 micrometers.

  In the present invention, such a plurality of conducting paths 51 (axial centers L10) are arranged so as to form an angle with respect to the perpendicular L20 of the main surface 50a of the film substrate 50 (that is, a plurality of conductive paths 51 in the thickness direction of the film substrate). This is a method of manufacturing an anisotropic conductive connector 60 having a structure in which a conductive path is penetrated and a plurality of conductive paths are inclined at a predetermined angle in a predetermined direction. Basically, a first step (described below) Including a step of creating a plurality of films with conductive wires, a second step (step of creating a block in which a plurality of films with conductive wires are integrated), and a third step (step of cutting the block).

[First step (step of creating a plurality of films with conductive wire)]
As shown in FIG. 1A, the insulating film 1 is wound around the outer periphery of the core material 4, and then one conductive wire 2 is wound around the outer periphery of the insulating film 1 in a spiral shape at a constant pitch (or On the contrary, one conductive wire 2 is first wound spirally at a constant pitch around the outer periphery of the core material 4, and then the insulating film 1 is wrapped so as to cover the conductive wire 2). A roll 5 (FIG. 1B) is created. Here, the winding can be performed by a known winding apparatus such as a horizontal alignment winding machine. Next, the wound material 5 (FIG. 1B) is heated and pressurized to integrate the insulating film 1 and the conductive wire 2 on the core material 4, and then from the core material 4. The roll-like product in which the insulating film 1 and the conductive wire 2 are integrated is removed, a part of the roll-like product is cut and developed into a flat product 6 (FIG. 2), and the flat product 6 is further removed. Is cut out, and a plurality of films with conductive wires are cut out.
FIG. 3A and FIG. 3B are specific examples of the plurality of films with conductive wires. In the film 10A with a conductive wire in FIG. 3A, the main surface 1a of the insulating film 1 is rectangular from the flat plate 6 (FIG. 2), and the direction of the conductive wire 2 (its axis) is insulating. The film 10B with the conductive wire in FIG. 3B is cut out so as to be inclined with respect to a predetermined one side (one side of the straight line) of the rectangular main surface 1a of the film 1. 2), the main surface 1a of the insulating film 1 is rectangular, and the direction of the conductive wire 2 (the axis thereof) is parallel and orthogonal to the sides (four sides) of the rectangular main surface 1a of the insulating film 1. It is cut out as follows. In addition, the dashed-two dotted line in FIG. 2 has shown the cutting line at the time of cutting out the film 10A with an electroconductive wire of FIG. 3 (a).

The film 10A with conductive wire in FIG. 3 (a) is perpendicular to the main surface 50a of the film substrate 50 of the conduction path 51 (axis L10) in the anisotropically conductive connector 60 (FIG. 11) to be finally manufactured. The angle (α) formed with L20 is the inclination angle of the conductive wire 2 (the axis thereof) in the film 10A with the conductive wire (the inclination angle (α1) with respect to a predetermined linear side of the main surface 1a of the insulating film 1). )) Is intended to be set in advance, and by using the conductive wire-attached film 10A, the subsequent third step (a plurality of conductive wire-attached films are integrated). In the step of cutting the block), a plane perpendicular to the predetermined linear end side of the block (one side derived from one side of the main surface 1a of the insulating film 1) is cut as a cross section. It is possible to obtain the anisotropic conductive connector 60 (FIG. 11) in which the plurality of conduction paths 51 are inclined at an angle (α) simply by cutting off.
On the other hand, when using the film 10B with the conductive wire of FIG. 3B, when cutting the block in the subsequent third step, the conductive wire 2 (the axis thereof) is perpendicular to the perpendicular of the cut surface. By setting the cut surface so as to form the angle (α), the anisotropic conductive connector 60 (FIG. 11) in which the plurality of conduction paths 51 are inclined at the angle (α) can be obtained.

  FIG. 4 is an enlarged view (FIG. 4 (a) is a perspective view, FIG. 4 (b) is a sectional view, and FIG. 4 (c) is a plan view) of the film 10A with a conductive wire. In the film with wire rod 10A, a plurality of conductive wire rods 2 arranged in parallel with each other at a constant pitch (d2) are fixed to the rectangular main surface 1a of the insulating film 1, and the plurality of conductive wire rods 2 (each axis thereof). The center L1) forms a predetermined inclination angle (α1) with respect to a predetermined linear side L2 of the main surface 1a of the insulating film 1 and is positioned in parallel with the main surface 1a. Here, “to form a predetermined inclination angle (α1)”, as shown in FIG. 4C, is the axis L1 of the conductive wire when the main surface 1a of the insulating film is viewed from vertically above. It means that the straight side L2 intersects at a predetermined acute angle (that is, not orthogonal or parallel). As described above, the predetermined inclination angle (α1) is such that the conduction path 51 (the axis L10) of the anisotropic conductive connector (FIG. 11) to be manufactured is on the main surface 50a (50b) of the film substrate 50. Applicable to the angle (α) formed with the perpendicular L20.

The insulating film 1 constitutes the film substrate 50 of the anisotropic conductive connector 60 (FIG. 11). Therefore, the material of the insulating film 1 is conventionally used for the film substrate of the anisotropic conductive connector. Known materials are used. That is, the material itself exhibits adhesiveness as it is or does not exhibit adhesiveness as it is, but is a material that can be bonded at least by pressure or heating, for example, a thermoplastic polyimide resin, an epoxy resin , Polyetherimide resins, polyamide resins, silicone resins, phenoxy resins, acrylic resins, polycarbodiimide resins, fluororesins, polyester resins, polyurethane resins, and other thermoplastic or thermosetting resins; polyurethane thermoplastic elastomers, polyester thermoplastics And thermoplastic elastomers such as elastomers and polyamide-based thermoplastic elastomers. Any of these resins and elastomers may be used alone or in admixture of two or more. In addition, various fillers, plasticizers, or rubber materials may be added to these resins and elastomers. Examples of the filler include SiO ₂ and Al ₂ O _3. Examples of the plasticizer include TCP (tricresyl phosphate) and DOP (dioctyl phthalate). Examples of the rubber material include NBS (acrylonitrile butadiene rubber) and SBS ( Polystyrene-polybutylene-polystyrene) and the like.

  Moreover, the thickness of the insulating film 1 is a main element that determines the pitch in one direction (pitch (D1) in the first direction in FIG. 11) in the film substrate of the conductive path of the anisotropic conductive connector, Generally, it is about 20-200 micrometers, Preferably it is about 20-150 micrometers.

  The conductive wire 2 constitutes a conduction path 51 of the anisotropic conductive connector 60 (FIG. 11), and the conductive wire 2 is made of a linear body made of a conductive material or made of the conductive material. A so-called insulated conductor, in which a linear body is provided with an insulation coating, is used. As the linear body made of a conductive material, a metal wire made of at least one metal (including an alloy) selected from gold, copper, aluminum, stainless steel, nickel, etc. is used from the viewpoint of electrical conductivity. In the case of using an insulated conductor, examples of the material used for the coating include the same materials as those exemplified as the material of the insulating film 1.

The cross-sectional shape of the linear body made of the conductive material is the above-described cross-sectional shape of the conduction path, and may be circular, polygonal, or other shapes, and is not particularly limited, but is preferably circular. Further, the diameter (thickness) of the linear body is the diameter (thickness) of the conductive path described above, and when the cross-sectional shape is circular, the diameter is preferably about 10 to 80 μm, particularly preferably about 12 to 60 μm. When the cross-sectional shape is a polygon or other shapes, the cross-section has a diameter (thickness) that corresponds to the area of a circle having a diameter within the above range. When using insulated conductors, the thickness of the insulation coating depends on the point of ensuring insulation between conductors (linear bodies), adhesion to the insulation film, and handling workability of insulated conductors (windings described below) From the viewpoint of workability, etc., it is generally about 0.5 to 10 μm, preferably about 1 to 5 μm.
In addition, the arrangement interval of the conductive wires 2 on the main surface 1a of the insulating film 1 in the film with conductive wires (that is, the pitch (d2) in FIGS. 4B and 4C) is different. This is applied to the other direction (pitch (D2) in the second direction in FIG. 11) in the film substrate of the conductive path of the conductive connector 60 (FIG. 11), and is set appropriately within the range of D2 described above. Is done.

The heating temperature and pressure in heating and pressurization for integrating the insulating film 1 and the conductive wire 2 on the core 4 in the first step constitute the conductive wire 2 and the insulating film 1. Although it differs depending on the material (in addition, when an insulated conductor is used as the conductive wire 2, the conductive wire 2 is easily fixed to the insulating film 1), the heating temperature is generally about 50 to 250 ° C., preferably Is about 100-200 ° C. Also, pressure is generally 2~30kgf / cm ² or so, preferably 3~20kgf / cm ² approximately.

  The wound material 5 (FIG. 1B) obtained by winding the insulating film 1 and the conductive wire 2 around the core material 4 is used as it is (that is, the insulating film 1 and the conductive wire 2 are used as the core material). It is preferable to arrange in a space where a reduced pressure or vacuum state can be formed (with 4), to make the space in a reduced pressure or vacuum state, and then perform the heating and pressurization. That is, before heating and pressurization, the wound material 5 (FIG. 1 (b)) is placed under reduced pressure or under vacuum, whereby the gaps between the core material 4, the insulating film 1 and the conductive wire 2 are obtained. Can be effectively reduced, and the durability (holding power of the conductive path) of the manufactured anisotropically conductive connector is improved. Here, the reduced pressure is a pressure smaller than the normal pressure, and generally means a pressure of (normal pressure−0.6 MPa) or less, and the vacuum is a pressure of (normal pressure−0.9 MPa) or less even in the reduced pressure. Means. In addition, it is more preferable to heat and pressurize in a vacuum from a viewpoint of removing a space | gap efficiently. The method for forming a reduced pressure or vacuum state is not particularly limited, but suction by a pump (vacuum pump) is preferable from the viewpoint of workability.

The space capable of forming the reduced pressure or vacuum state is, for example, a rigid box (that is, a box body having rigidity capable of maintaining its shape without being deformed itself when the reduced pressure or vacuum state is formed. ) And an internal space of a bag made of a flexible film. Examples of the material of the rigid box include metals such as iron, aluminum, stainless steel, carbon steel, and bronze, and plastics such as polyethylene, polyurethane, acrylic resin, polyamide, and polycarbonate. As the flexible film, a metal film such as aluminum, a nylon film, a polyester film, a polyethylene film, a plastic film such as a polyimide film, a laminate film obtained by laminating an aluminum film or the like on a polyethylene film, or the like can be used.
If a bag made of a flexible film is used, when the internal space is evacuated, the bag closely adheres to the wound material 5, so that the voids can be more effectively removed.

  In addition, in the pressurization when performing the heating and pressurization, it is preferable to apply a uniform pressure to the core material so that the winding state (pitch, winding direction, etc.) of the conductive wire is not disturbed, From such a viewpoint, a method of introducing a compressed gas into the above-described space (a space where a reduced pressure or a vacuum state can be formed) is preferable. In the case of this method of introducing a compressed gas, it is more preferable to use an inert gas such as nitrogen gas as the compressed gas because oxidation of the conductive wire can be suppressed.

[Second step (step of creating a block in which a plurality of films with conductive wires are integrated)]
In the second step, the plurality of films with conductive wires prepared in the first step are stacked so that the conductive wires 2 of adjacent films are parallel to each other, and the resulting stack is heated and pressed. To create a block in which a plurality of films with conductive wires are integrated. Such heating and pressurization is a process of fusing at least the insulating film to the conductive wire between the adjacent films with the conductive wire, preferably the insulating film is fused to the conductive wire, and Then, heating and pressurization are performed so that the insulating films are fused.
In the above heating and pressurizing treatment, the heating temperature is generally selected in the range of the softening point of the resin (elastomer) constituting the insulating film to about 300 ° C. (specifically, 50 to 300 ° C.). In addition, when a thermosetting resin is used for the insulating film 1, it is preferable to heat at a temperature lower than the curing temperature. Also, pressure is generally 5~30kgf / cm ² or so, preferably 5~20kgf / cm ² approximately.

  5 to 7 show a conductive structure in which the plurality of conductive wires 2 (the axis L1 thereof) are inclined at an angle (α1) with respect to a predetermined linear side L2 of the main surface 1a of the insulating film 1. 10A (FIG. 3 (a), FIG. 4) with conductive wires are stacked so that the linear sides L2 of adjacent insulating films 1 overlap in parallel (FIG. 5), and the stack obtained in this way 20 shows a state in which a block 30 (FIG. 7) is created by heating and pressurizing 20 (FIG. 6).

  As shown in FIG. 7, in the present invention, in the second step, a plurality of films 10A with conductive wires are integrated, and a plurality of films arranged in parallel with each other in the vertical (stacking direction) and horizontal directions are arranged. A block 30 having a structure in which an insulating resin R is interposed between the conductive wires 2 is formed.

  In addition, the space | interval (in FIG. 7) of the conductive wire 2 in the direction (arrow B2 direction in FIG. 7) corresponding to the stacking direction (arrow B1 direction in FIG. 6) of the film 10A with a conductive wire in a block. d1) is applied to one direction (pitch (D1) in the first direction in FIG. 11) in the film substrate of the conductive path 51 of the anisotropic conductive connector 60 (FIG. 11). That is, the thickness of the insulating film 1 (when using an insulated conductor for the conductive wire 2, the thickness of the insulating film 1 and the thickness of the insulating resin coating layer), and heating and The pitch (D1 in FIG. 11) in one direction (first direction) in the film substrate of the conductive path 51 of the anisotropic conductive connector 60 (FIG. 11) is determined by the conditions (temperature, pressure) of the pressure treatment. Is done.

  In the second step, as described above, the stack of the plurality of films with conductive wires is heated and pressurized to create a block in which the plurality of films with conductive wires are integrated. Also in the process, prior to heating and pressurization, a stack of a plurality of films with conductive wires is placed in a space where a reduced pressure or vacuum state can be formed, and the inside of the space is put under reduced pressure or a vacuum state, and thereafter The heating and pressurization are preferably performed. By doing in this way, it is possible to remove the gaps between the films with conductive wire that overlap vertically, and when gaps remain in the film with conductive wires, this gap can be removed, preferable. Here, the reduced pressure or vacuum is synonymous with that in the first step, and the space capable of forming the reduced pressure or vacuum state is also an internal space of the rigid box or a bag made of a flexible film. Internal space can be used. The method for forming a reduced pressure or vacuum state is not particularly limited, but suction by the pump is preferable from the viewpoint of workability. Also in the second step, as in the first step, it is preferable to use a bag made of a flexible film in order to form a reduced pressure or vacuum state. If a bag made of a flexible film is used, when the internal space is evacuated, the bag is in close contact with the stack, and the voids between the stacked films with conductive wires are more effectively removed. be able to.

  Further, more preferable results can be obtained if the heating and pressurizing treatment in the second step is performed as follows. That is, as shown in FIGS. 9 and 10, the stack 20 has a heat resistance of such a size that a slight gap is formed between the inner surface of the stack 20 and the stack 20 when the stack 20 is accommodated. It is a box, and it accommodates in the box 40 which has the opening 41 for taking in / out the stacking body 20, and in this state (state of FIG. 10), the stacking body 20 with the heat resistant box 40 is the above-mentioned. The stacked body 20 at the time of pressurization is disposed in the internal space of the bag body made of the flexible film, and the space 20 is depressurized or evacuated and then heated and pressurized. The positional deviation between the plurality of films 10A with conductive wires constituting the structure can be prevented, and the uniformity of the inclination direction and the inclination angle of the plurality of conductive wires (conduction paths) in the manufactured anisotropic conductive connector is increased. The “slight gap” refers to a gap of about 0.5 to 20 mm between the side surface of the stack and the inner side surface of the box. Also. “Heat resistance” in a heat-resistant box means that the heat-resistant box is not deformed or softened (melted) during the heat treatment, and specific examples of the heat-resistant box include aluminum ( Hereinafter, a metal box made of iron, stainless steel, or a ceramic box may be used.

[Third step (step of cutting the block)]
The third step is a step of obtaining an anisotropic conductive connector by cutting the block created in the second step into a predetermined film thickness with a plane intersecting the conductive wire at an angle. FIG. 8 shows a conductive wire rod-attached film 10 </ b> A (FIG. 3) in which the conductive wire rod 2 (the axis L <b> 1) is inclined at an angle (α <b> 1) with respect to the linear side L <b> 2 of the main surface 1 a of the insulating film 1. This is an example in which the block 30 (FIG. 7) obtained by stacking (a) and FIG. 4) is cut.

  In FIG. 8, the cutting tool 3 shows a blade, but the cutting tool 3 is not limited to a blade as long as it can cut out a film from the block. Various cutting tools (wire saw, slicer, plane, laser, etc.) Etc.) can be used.

  In the example of FIG. 8, a predetermined linear end L2 derived from a predetermined linear one side L2 (see FIGS. 4 to 6) of the main surface 1a of the insulating film 1 in the film with the conductive wire in the block 30. The block 30 is cut so that a plane 30b perpendicular to the line 'becomes a cut surface. That is, as a film with a conductive wire, the conductive wire 2 (its axis L1) is inclined at an angle (α1) with respect to a predetermined linear side L2 of the main surface 1a of the insulating film 1. By using the attached film 10A (FIG. 3 (a), FIG. 4), the end side L2 ′ of the block 30 derived from the predetermined linear side L2 of the main surface 1a of the insulating film 1 is used as a reference. By cutting the block 30 so that the plane 30b perpendicular to the cut surface becomes a cut surface, the inclination angle of the conductive wire 2 set in the film 10A with the conductive wire (predetermined on the main surface 1a of the insulating film 1) The film substrate of the conductive path 51 (axial center L10) in the anisotropically conductive connector 60 (FIG. 11) manufactured without changing the inclination angle (α1) of the axial center L1 of the conductive wire 2 with respect to the straight side L2. 50's This is an angle (α) formed with respect to the perpendicular L20 of the main surface 50a. Therefore, in the cutting operation, it is easy to set the cut surface, the plurality of conduction paths are inclined at a target inclination angle, and the inclination direction between the plurality of conduction paths is highly uniform (the plurality of conduction paths are constant). It is possible to reliably manufacture anisotropic conductive connectors that are inclined in the same direction. Further, since the film size (product size) obtained by cutting is unified, there is no problem that the yield is greatly reduced.

  On the other hand, the conductive wire material (axial center) is inclined to the linear side of the main surface of the insulating film, such as the film 10B with conductive wire material (FIG. 3B), on the film with conductive wire material. When an anisotropic conductive connector is cut out from a block made from a non-processed block, the angle formed by the conductive wire (the axis thereof) with respect to the perpendicular to the cut surface is the same as that in the anisotropic conductive connector 60 (FIG. 11). Based on the direction of the conductive wire (axis), the cut surface of the conduction path 51 (axis L10) is equal to the angle (α) formed with respect to the perpendicular L20 of the main surface 50a of the film substrate 50. Set up.

  In the manufacturing method of the present invention, as described above, a plurality of films with conductive wires (one row) having a plurality of conductive wires arranged in parallel at the same pitch (each from a film with conductive wires having a large size). Since the anisotropic conductive connector is cut out from the block in which the cut substantially the same thing) is stacked, the insulated conductor in the winding block obtained by multiply winding the conventional insulated conductor ( Uneven winding direction of the metal wire) can prevent the problem that the direction of inclination of the conducting path in the anisotropic conductive connector is not uniform, and the plurality of conducting paths are inclined at a predetermined inclination angle and the plurality of conducting paths are inclined. An anisotropic conductive connector having a small variation in the inclination direction between the passages can be easily manufactured. Moreover, the film size of the anisotropically conductive connector cut out after the cutting, adjusting the position of the block and the cutting blade in consideration of the direction of the wire (the axis) in the block, as in the past, Since it is not necessary to perform post-processing to unify the product size, the complexity of the manufacturing operation can be eliminated. Therefore, it is possible to manufacture an anisotropic conductive connector having a desired size (film size (product size)) having high connection reliability to a connection target (circuit board, semiconductor element) with a high yield.

  In addition, although the above demonstrated the method of this invention exemplifying the film with an electrically conductive wire with the external shape (main surface external shape) of an insulating film, in this invention, the external shape of the insulating film in the film with an electrically conductive wire May have a shape other than a rectangle. However, as can be understood from the above description, the main surface of the insulating film in the film with a conductive wire has a linear shape that can define the inclination angle of the conductive wire, such as a rectangle (outer shape). It goes without saying that is preferable.

  Also, anisotropic conductive connectors are often used in general applications (mounting connectors, inspection connectors (especially inspection connectors)) whose overall shape (outer shape of the film substrate) is rectangular. Therefore, also in this invention, it is preferable to make the external shape of the insulating film in a film with a conductive wire into a rectangle so that the rectangular anisotropic conductive connector can be obtained only by slicing (cutting) the block.

  In the above description, the manufacturing method of the present invention has been described with reference to the anisotropic conductive connector 60 in which the arrangement state of the conduction paths 51 shown in FIG. 11 is a square matrix. In the production of a stack of films with conductive wires, each conductive wire in an odd-numbered film with conductive wires is stacked evenly. What is necessary is just to stack so that it may be arrange | positioned in the clearance gap between the conductive wire materials of an attached film.

  Further, in the present invention, the whole conductive path or the end of the specific part of the conductive path protrudes or is recessed from the main surface of the film substrate, and for each conductive path, only one or both of the main paths of the film substrate are used. When manufacturing an anisotropic conductive connector of a type protruding or recessed from the surface, the following processing is performed after the first to third steps.

When projecting the end of the conductive path from the main surface of the film substrate, there is a method of selectively removing the peripheral part of the conductive path from which the end of the film substrate should be projected. Specifically, wet etching using an organic solvent, plasma etching, dry etching using an argon ion laser, a KrF excimer laser, or the like is used alone or in combination. The organic solvent is appropriately selected depending on the material of the coating layer of the film substrate or the insulated conductor, and examples thereof include dimethylacetamide, dioxane, tetrahydrofuran, and methylene chloride.
Further, metal can be deposited and projected at the end (end surface) of the conductive path to be projected by plating or vapor deposition. When such metal deposition is performed, the metal may be the same as or different from the metal constituting the conductive path. A suitable example is a Ni / Au layer formed by electroless plating. By providing the Ni / Au layer by electroless plating, there is an advantage that the contact resistance with the terminal of the connection object (electronic component, circuit board, etc.) can be kept low.

  As a method for indenting the conduction path from the surface of the film substrate, a method of selectively removing only the conduction path exposed on the surface of the film substrate is employed, and specifically, chemical etching using acid or alkali is employed. .

  The protruding amount of the conductive path (height from the main surface of the film substrate to the leading surface of the conductive path) is generally selected from the range of 5 to 60 μm.

  The anisotropic conductive connector produced in the present invention is particularly preferable as a connector for inspection. From this point, the elastic modulus of the entire structure is preferably 5 to 100 MPa at 0 to 50 ° C., and preferably 5 to 70 MPa. Are particularly preferred. The elastic modulus of the entire structure is measured using a dynamic viscoelasticity measuring device (DMS210, manufactured by Seiko Instruments Inc.). The measurement condition is that the temperature is raised at 5 ° C./min at a constant frequency (10 Hz) in a tensile mode with respect to one direction in which the surface of the film substrate of the anisotropic conductive connector expands −30. It is set as the measurement in ° C-250 ° C. The thickness of the sample input at the time of measurement is the thickness of the film substrate in the anisotropic conductive connector 60 (FIG. 11) (symbol T in FIG. 11).

  Elements that determine the elastic modulus of the entire structure of the anisotropic conductive connector 60 (FIG. 11) include the material of the conduction path 51, the thickness (diameter), the cross-sectional shape, the inclination angle, the pitch, and the like, and the material of the film substrate And thickness. Therefore, in the method for manufacturing the anisotropic conductive connector of the present invention, by adjusting these values, the elastic modulus of the entire structure of the anisotropic conductive connector obtained is within the range of −30 to 250 ° C. It is preferable to set the pressure at 5 to 70 MPa at 0 to 50 ° C.

Hereinafter, the present invention will be described in more detail by describing examples and comparative examples.
(Example 1)
An aluminum cylindrical core with a diameter of 320 mm and a length of 270 mm is attached to a horizontal alignment winding machine HPW-02 (manufactured by Nittoku Engineering Co., Ltd.), a 50 μm-thick fluororesin film as a release film, and rubber hardness on it One layer of a film made of a thermoplastic polyurethane elastomer (Esmer URS, manufactured by Nippon Matai Co., Ltd., softening point 60 ° C.) having a thickness of 75 ° and 100 μm is wound, and then a 29 μmφ heat-resistant polyurethane-coated wire (25 μmφ copper wire is coated with heat-resistant polyurethane) Was coated with a thickness of 2 μm) and wound 250 mm at a winding interval (pitch) of 100 μm. Further, a fluororesin film having a thickness of 50 μm was wound as a release film so as to cover the wound wire rod, and an aluminum plate having a thickness of 1 mm as a backing plate was further arranged along the cylindrical shape of the core.

A heat-resistant nylon film (WL8400-003-60-1000-SHT9, manufactured by Airtech, softening point: 220 ° C.) having a size of 1000 mm × 1530 mm and a thickness of 80 μm and a seal tape GS213 (made by Airtech) A bag body that can be formed is prepared, and in the bag body, the above-described core, film, and wire wound material and a backing plate are arranged in an integrated state, and the film space is sealed. The film space was vacuumed by suction with a vacuum hose (connected to a vacuum pump). And the bag body which accommodated this winding and the contact plate, maintaining this vacuum state, was thrown into the autoclave apparatus (made by Iwata Manufacturing Co., Ltd.) which can be heated and pressurized. After the charging, the inside of the tube is heated so that the core temperature becomes 155 ° C. (inside tube temperature: 200 ° C.), and pressurized with nitrogen gas so that the pressure in the tube becomes 10 kgf / cm ^2. After the pressure in the tube reached the target value, the tube was held for about 30 minutes for cooling. After the temperature reached 70 ° C., the pressure was released.

  After that, the bag containing the wound product composed of the core, film and wire is taken out from the autoclave, the wound product is taken out from the bag, the core is removed, and the thermoplastic urethane elastomer film and the heat-resistant urethane coated wire are removed. The roll-shaped block which integrated was obtained.

Next, one side of the roll-shaped block is cut into a flat plate, and with a Thomson blade, from the flat plate to the main surface of a rectangular thermoplastic urethane elastomer film having a size of 120 mm × 62 mm, the pitch is 100 μm. A plurality of heat-resistant urethane-coated wires arranged in parallel with each other are arranged in the state shown in FIG. 4C, that is, in a state where they are arranged and fixed at an inclination angle (α1) of 15 degrees with respect to the linear side L2 of the thermoplastic urethane elastomer film. 22 films with a wire rod were cut out. Next, the 22 films with wire rods were stacked in the vertical direction as shown in FIG. 5, and the stack was put in an aluminum box as shown in FIGS.
The aluminum box has an opening on the top surface through which the stack can be put into the interior as it is, has a depth that can completely accommodate the stack, and has an inner surface and a side surface of the stack (heat A box having a rectangular parallelepiped shape, in which a gap of 1.5 mm is formed with the side surface of the plastic urethane elastomer film, was used.

Next, an aluminum plate having a thickness of 10 mm and a size of 120 × 62 mm was placed in the box from the opening on the upper surface of the aluminum box and placed on the uppermost surface of the stack. In this state, the aluminum box containing the stack is placed inside a bag made of nylon film that can form the vacuum space used above, and the film space is kept in a vacuum state, and the vacuum state is maintained. However, it is put into an autoclave apparatus (manufactured by Iwata Manufacturing Co., Ltd.) capable of heat and pressure treatment, and heated so that the temperature of the aluminum box is 175 ° C. (the temperature in the tube is 200 ° C.). Pressurization was performed with nitrogen gas so as to be 15 kgf / cm ² . After the tube temperature and pressure reached the target values, the tube was cooled. As a result, a block in which the stack was integrated was formed.

  The created block is cut with a wire saw (F-600, manufactured by Yasunaga Co., Ltd.) with respect to a predetermined end of the block (an end derived from the linear side L2 of the thermoplastic urethane elastomer film). 200 anisotropically conductive connectors having a film substrate thickness of 100 μm and a size of 120 mm × 60 mm were cut out so that the planes were orthogonal to each other.

  From the 200 anisotropically conductive connectors obtained above, 5 samples are arbitrarily sampled, and for each, from the two cross-sectional directions of the anisotropically conductive connector, the length of the conduction path is determined with a length measuring microscope (manufactured by Olympus Corporation). The variation of the tilt angle was examined respectively. That is, the first cross section cut in the direction orthogonal to the main surface of the film substrate and the second cross section cut in parallel to the main surface of the film substrate were observed with a length measuring microscope. As a result, the variation in the tilt direction (angle variation in the tilt direction) for all the conductive paths in the cross section from the observation of the second cross section is 0.15 degrees, and the variation in the tilt angle from the observation of the first cross section is 0. It was found to be 22 degrees.

(Comparative Example 1)
Using a winding device, a 25 μmφ copper wire coated with a 2 μm thick thermoplastic polyurethane elastomer used in the above example is used to form a prismatic plastic core having a total length (winding width) of 640 mm and a cross-sectional shape of 160 mm × 160 mm square. The material was aligned and wound to form a winding coil having the average number of windings per layer of 3500 turns and a winding number of 150 layers (= layer thickness of about 12 mm). The obtained rolled coil was heated to about 150 ° C. and pressurized with 10 kgf / cm ² to fuse the thermoplastic polyurethane elastomer, cooled to room temperature, and the wound wires were integrated with each other. A wound coil block was obtained. This winding coil block is sliced into a block shape with a band saw as a cross section with a surface that forms an inclination angle of 15 degrees with a wound wire rod, and is a front stage of an anisotropic conductive film having a size of 120 mm × 180 mm and a thickness of 10 mm Got the block. The obtained block was sliced with a wire saw, the outer diameter was finished, and 2800 anisotropic conductive connectors having a size of 10 mm × 120 mm and a thickness of 100 μm were produced.

  From the 2800 anisotropic conductive connectors obtained above, 5 samples were arbitrarily sampled, and each of the conductive paths of the anisotropic conductive connectors was measured with a length measuring microscope from two cross-sectional directions of the anisotropic conductive connectors in the same manner as in the above embodiment. The variation of the tilt direction and tilt angle was examined respectively. As a result, the variation in the tilt direction (angle variation in the tilt direction) was 0.45 degrees, and the variation in the tilt angle was 0.35 degrees.

  Using the anisotropic conductive connectors prepared in Example 1 and Comparative Example 1, a connection test (continuity test) between the electronic component and the circuit board described below was performed.

[Specifications of evaluation electronic components]
Component size: 9.6 mm x 7.0 mm x 1.65 mm (thickness)
Electrode size: 1.0mm x 0.8mm
Number of electrodes: 12 Intermediate pitch in electrode arrangement: 1.8 mm

[Evaluation circuit board specifications]
Base material: Glass epoxy base material (FR-4)
Total thickness including circuit pattern: 1mm
Ratio of the circuit width of the circuit pattern to the width of the interval portion: (1.0 mm: 0.8 mm)

〔Evaluation methods〕
Whether an anisotropic conductive connector is interposed between the evaluation electronic component and the evaluation circuit board, and a contact load of 25 N is applied from the electronic component side so that all terminals (electrodes) of the electronic component are electrically connected to the circuit board. (That is, whether all the points conduct). This test is then repeated 10 times.

〔result〕
When the anisotropic conductive connector of Comparative Example 1 was used, it was conducted 8 times at all points in 10 tests. On the other hand, when the anisotropic conductive connector of Example 1 was used, all points were conducted 10 times in 10 tests.
From this result, the anisotropic conductive connector obtained by the manufacturing method of the present invention has a small variation in the inclination direction between the plurality of conduction paths (direction of the conduction path), and has good contact with the connection object. It can be seen that this is an anisotropic conductive connector with high connection reliability.

  As is clear from the above description, according to the present invention, the variation in the inclination direction (direction in which the conduction path is formed) between the plurality of conduction paths is small, the contact property with the connection object is good, and the connection object is obtained. It is possible to efficiently manufacture an anisotropic conductive connector that can obtain high connection reliability. Furthermore, an anisotropic conductive connector that can obtain high connection reliability with such a connection object can be manufactured in a desired film size and with a high yield.

In the first step of the present invention, a perspective view (FIG. (A)) of an operation of winding an insulating film around a core material and further winding a conductive wire, and a perspective view of a wound material obtained by the operation (FIG. (B) )). It is a top view of the flat material obtained by expand | deploying the roll-shaped material formed by integrating an insulating film and an electroconductive wire. FIG. 3A and FIG. 3B are plan views of a plurality of films with conductive wires obtained by cutting a flat plate. It is a perspective view (Drawing 1 (a)), a sectional view (Drawing 1 (b)), and a top view (Drawing 1 (c)) of a film with an electroconductive wire. It is a perspective view which shows the operation | work which piles up a film with an electroconductive wire (FIG. 4). FIG. 5 is a perspective view of a stack obtained by stacking films with conductive wires (FIG. 4). It is a perspective view of the block which integrated the stacking body (FIG. 6) by heating and pressurization. It is a perspective view of the operation | work which cuts out a film from a block (FIG. 7). It is a perspective view which shows a mode that a stacked body (FIG. 6) is put into a heat resistant box. It is a perspective view which shows the state in which the stack (FIG. 6) was accommodated in the heat resistant box. It is a top view (Drawing 11 (a)) and a sectional view (Drawing 11 (b)) of an anisotropic conductive connector manufactured by the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insulating film 1a Main surface of insulating film 2 Conductive wire L1 Axis center of conductive wire L2 Straight side α1 Inclination angle 10A, 10B Film with conductive wire

Claims (8)

A method of manufacturing an anisotropic conductive connector having a structure in which the axes of a plurality of conduction paths penetrating in the thickness direction of a film substrate form an angle with respect to a perpendicular to the main surface of the film substrate, and is insulated on the outer periphery of a core material A conductive film is wound, and then a conductive wire is spirally wound around the outer periphery of the insulating film at a constant pitch, or a conductive wire is wound around the outer periphery of the core material at a constant pitch, and then the conductive wire is wound After winding the insulating film so as to cover, heat and pressure are applied to integrate the insulating film and the conductive wire on the core, and then the insulating film and the conductive wire are The roll-like product obtained by the integration is removed from the core material, and this is cut into a flat product, and then a plurality of films with conductive wires are cut out from the flat product. Between films adjacent to each other with a conductive wire The conductive wires are stacked so that they are parallel to each other, and the resulting stack is heated and pressurized to create a block in which a plurality of films with conductive wires are integrated. A method for manufacturing an anisotropic conductive connector, wherein an anisotropic conductive connector is obtained by cutting a plane that intersects with a conductive wire at an angle to a predetermined film thickness. The plurality of films with conductive wires are shaped so that the main surface of the insulating film has a straight side, and the axis of the plurality of conductive wires has a predetermined inclination angle with respect to the straight side. In addition, a plurality of films with conductive wires are stacked so that the linear sides of adjacent insulating films are stacked in parallel to form a stack, and the blocks obtained from the stack are further insulated. The anisotropic conductivity according to claim 1, wherein the anisotropic conductive film is cut to a predetermined film thickness with a cross section taken as a cross section of a plane perpendicular to the linear end side of the block derived from one linear side of the main surface of the conductive film. A method for manufacturing a connector. The insulating film and the conductive wire wound around the core material are placed in a space where a reduced pressure or vacuum state can be formed together with the core material, and the space is reduced in pressure or vacuum, and then heated and pressurized. The method for manufacturing an anisotropic conductive connector according to claim 1, wherein the insulating film and the conductive wire are integrated on the core material. The method for manufacturing an anisotropic conductive connector according to claim 3, wherein the space capable of forming the reduced pressure or vacuum state is an internal space of a bag body made of a flexible film. The method for manufacturing an anisotropic conductive connector according to claim 3 or 4, wherein the pressurization is performed by introducing a compressed gas into a space where the reduced pressure or vacuum state can be formed. 6. The stack according to claim 1, wherein the stack is disposed in a space where a reduced pressure or vacuum state can be formed, and the stack is heated and pressurized after being reduced in pressure or vacuum. A method for manufacturing the anisotropically conductive connector according to claim 1. The method for manufacturing an anisotropic conductive connector according to claim 6, wherein the space capable of forming a reduced pressure or a vacuum state is an internal space of a bag body made of a flexible film. The stack is accommodated in a heat-resistant box having a size such that a slight gap is formed between the inner surface of the stack and the side of the stack. The stack is placed in an internal space of a bag made of a flexible film together with the body, and the stack is heated and pressurized after being reduced in pressure or vacuum. Method for manufacturing an anisotropic conductive connector.

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